Retinoic acid and its natural and synthetic analogs exert a wide variety of biological effects. They have been found to affect cellular growth and differentiation and are promising agents for the treatment of several cancers.
U.S. Pat. No. 5,618,839 discloses a series of substituted (5,6)-dihydronapthalenyl compounds of the formula ##STR2## or nontoxic pharmaceutically acceptable salts, physiologically hydrolyzable esters or solvates thereof, in which
X is --O--CO--, --NH--CO--, --CS--NH--, --CO--O--, --CO--NH--, --COS--, --SCO--, --SCH.sub.2 --, --CH.sub.2 --CH.sub.2 --, --C.tbd.C--, --CH.sub.2 --NH--, --COCH.sub.2 --, --NHCS--, --CH.sub.2 S--, --CH.sub.2 O--, --OCH.sub.2 --, --NHCH.sub.2 -- or --CR.sup.5 .dbd.CR.sup.6 --;
R.sup.m and R.sup.k are independently hydrogen, halogen, C.sub.1-6 alkyl, hydroxy, C.sub.1-6 alkyloxy or nitro;
n is zero or one;
R.sup.4 is --(CH.sub.2).sub.t --Y, C.sub.1-6 alkyl, or C.sub.3-6 cycloalkyl;
R.sup.1 is --CO.sub.2 Z, C.sub.1-6 alkyl, CH.sub.2 OH, --CONHR.sup.y, or --CHO;
R.sup.2 and R.sup.3 are independently hydrogen or C.sub.1-6 alkyl;
R.sup.a and R.sup.b are independently hydrogen or C.sub.1-6 alkyl; but when n is one, R.sup.a and R.sup.b together can form a radical of the formula ##STR3## Y is naphthyl or phenyl, both radicals can be optionally substituted with one to three same or different C.sub.1-6 alkyl or halogen;
Z is hydrogen or C.sub.1-6 alkyl;
R.sup.5, R.sup.6 and R.sup.y are independently hydrogen or C.sub.1-6 alkyl; and
t is zero to six.
These compounds are reported to have retinoid-like activity and to be useful for preventing and/or treating various skin disorders such as acne, psoriasis and damage from irradiation, for treatment of various tumors and non-malignant proliferative skin diseases and for treatment of rheumatic diseases such as rheumatoid arthritis.
U.S. Pat. No. 5,534,261 discloses that retinoids, particularly all-trans retinoic acid, can be used to minimize or prevent adhesion formation following surgery.